| The NEPE propellant with high-level nitramine explosive and nitrate ester shows different aging characteristics with that of the classic AP/Al/HTPB propellant. Therefore, the investigation of the NEPE propellant's themal aging propetis and the predication of the propellant's storage life are necessary.The thermal accelerated aging characteristics of the N-15B propellant were investigated.The mass loss properties of N-15B propellant at different aging temperature were studied. The results indicated that the percent of mass loss increased rapidly at forepart, then incressed. The temperature in the storage had obviously affection on the mass loss properties of N-15B propellant.The correlations of explosive heat with aging time of N-15B propellant were mensurated by HR3000 calorimetric bomb. The experimental results showd that the explosive heat was decreased along with the aging time. The temperature had less affection on the explosive heat.The hardness, the gel fraction and the relative cross-linking density of the aged propellant samples were measured. The results showed that the hardness, the gel fraction and the relative cross-linking density increased with the aging time and aging temperature at forepart, but decreased then. The effects of temperature on the aging characteristics of the propellant are different at various aging temperature. At 50°C and 60°C, the aging curves of the propellant property descend slowly, and had the analogical shape. At 70°C, the properties of the propellant degraded rapidly. That indicated the temperatue over 70°C is not suitable for the storage of the N-15B propellant.Based on the accelerated aging experimental results, the reasons of the N-15B propellant performanes degradation are that the volatilization and migration of the plasticizers nitrate ester, the continued-curing reaction of binder system and the decomposition products of the nitrate ester on the degradation of N-15B propellant's polymer.
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